Clem O. Mayer, age 84, of New Holstein, passed away Wednesday, July 22, 2020, at St. Luke's Medical Center in Milwaukee due to heart failure. He was born November 25, 1935, in Manitowoc County to Gottfried H. & Clara P. (Buhl) Mayer. Clem attended St. Gregory's Grade School in St. Nazianz and graduated from Valders High School in 1953. He served in the US Army. On April 4, 1959, he married Donna Ahrens at St. Gregory's Catholic Church in St. Nazianz. Clem worked at Arps Corp which became Amerequip until his retirement. He was a member of Holy Rosary Catholic Church in New Holstein, served on the New Holstein School District board for 21 years serving in several capacities, and very active in coaching youth baseball and Boy Scouts. He enjoyed watching his children and grandchildren participating in sports and other extra-curricular activities. In his spare time, he could be found working in his garage and basement building woodworking projects. Clem was an avid reader and played a lot of games of Solitaire. Survivors include his wife, Donna of New Holstein; his 11 children, Greg (Ann) Mayer of Milwaukee, David Mayer of Luxemburg, Denis (Donna) Mayer of New Holstein, Alan (Jessica) Mayer of Sheboygan Falls, Thomas (Jessica) Mayer of Denver, CO, Kim (Shane) Wixom of Fort Worth, TX, Debra (Thomas) Pennings of Appleton, Tammy (Dennis) Butz of Kewaskum, Daniel (Anne) Mayer of Wheaton, IL, Jennifer (Troy) Schneider of Reedsburg, and Jason Mayer of Fond du Lac; 28 grandchildren, Catherine (Fiance', Luke) and Matthew Mayer, Eric (Jessica) and Kurt (Samantha) Mayer, Shania Mayer (special friend, Bryce) and Skyler Vandenack, Jacob and Piper Kruchoski, Nathan and Jaclyn Mayer, Kirstie (Derek) Leslie and Jacob Wixom, Bradley and Benjamin Pennings, Alyssa, Nicole, and Andrea Butz, Clare (Fiance', Anthony), Regina, Lydia, Lucy, Paul, Daniel, Cecilia, and John Mayer, Ryan, Caden, and Ethan Schneider; four great-grandchildren, Ryker and Owen Mayer, Hadlee and Tinlee Leslie. He is further survived by brothers-in-law; sisters-in-law; nieces; nephews; other relatives; and friends. Preceding him in death were his parents; his brother, Harold (Dorothy) Mayer; and his sister, Lenore Sauer. A Liturgy Mass of Christian Burial will be held at 1:00 PM on Saturday, August 1, 2020, at Holy Rosary Catholic Church, 1724 Madison Street, New Holstein, WI 53061. Visitation: Family and friends may visit with Clem's family at the Sippel Funeral 2618 Altona Avenue, New Holstein, WI on Saturday, August 1st from 10:00 AM until 12:30 PM. A memorial fund will be established in his name. For further details, please contact the Sippel Funeral Home in New Holstein (920) 898-4300 or visit www.sippelfuneralhome.net.